If you picnic in a Texas park, chances are you’ll encounter fire ants — a kind of pest that can deliver painful bites. This invasive (入侵的) species, like many others, is not only annoying but also destructive.
An invasive species is any kind of living thing that isn’t native to an ecosystem and causes harm. Sometimes non-native species are imported by accident, like in the 1930s when ships from South America inadvertently took fire ants to North America. Other times non-native species are imported deliberately. Some types of Asian fish that were originally imported to the U.S. from China to clean fish farms escaped and entered rivers. Green iguanas were brought to China, as pets, but irresponsible owners released them.
Non-native species have even been imported for emotional reasons. A man once released dozens of European starlings (八哥) in New York in an effort to bring all the birds mentioned in Shakespeare’s writings to America. Today, millions of starlings cause over $800 million in damage to U.S. agriculture every year. Invasive species’ global economic influence is also enormous. The U.S. government assesses that invasive species cost the American economy over $120 billion every year.
Invasive species can damage their host habitats by unbalancing local ecosystems. They often lack natural enemies in their new environment and out-compete native species for food and other resources. They also might feed on local species. Invasive species can also carry diseases for which local species have no immunity (免疫力). This can result in the loss of an entire native species.
Invasive species are among the leading threats to native wildlife. About 42% of threatened or endangered species are at risk due to invasive species. Unless people take serious action, the economic and environmental costs of invasive species will become disastrous.
1. What does the underlined word “inadvertently” mean in paragraph 2?A.Separately. | B.Regularly. |
C.Temporarily. | D.Unexpectedly. |
A.To satisfy his wish. |
B.To raise them as pets. |
C.To copy Shakespeare’s behavior. |
D.To do agricultural experiments. |
A.Food shortage for native people. |
B.Serious economic imbalance. |
C.Economic and environmental problems. |
D.Dangerous diseases for humans. |
A.Wildlife Conservation |
B.Protecting Native Species |
C.Environmental Protection Measures |
D.Our Unwelcome Guests |
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【推荐1】France is experiencing an unusually mild winter, which has led to low snowfall in ski areas across the country.
One affected ski area is Le Mourtis, in the Pyrenees mountains of southern France. The lack of snow has forced the holiday village to temporarily close its ski runs—at the height of the winter season. Local restaurants and hotels are seeing fewer visitors. People who do come to the area are seeking to do other things besides skiing. Warmer temperatures have made hiking one of the most popular activities. Recent daytime temperatures at Le Mourtis have reached 10 degrees Celsius. Some hikers even removed winter clothing while making their way across mountain areas containing very little snow.
“Skiing? No one today can guarantee it,” said hotel operator Gillaizeau. He has been making money by renting out two-wheeled motorcycles to help visitors in the area have fun. The scooters can be ridden down grassy mountains. They come with equipment made for riding on snow, but Gillaizeau has attached bicycle wheels instead. His ski rental equipment remains untouched. He says he has had to reduce the hours of some workers and expects business losses during the season to drop as much as 15 percent.
Many people in the area believe the latest winter is more than just a bad year. The last time France experienced such a mild December and January was in 1900, French weather officials say. Christelle Robert is an official with Meteo-France, the country’s national weather service. She told Reuters that mild winters and less snow seem to be a clear sign of global warming.
Scientists have predicted a continued rise in world temperatures. People connected to the area’s ski industry are considering a future with much less snow. If such weather continues, ski resorts around 1,600 meters above sea level will be so warm that they will not even be able to use artificial snow because it will melt.
1. Why did some hikers take off their winter clothes while crossing mountains?A.They were wearing too thick clothes. | B.They had been exercising too much. |
C.The mountain roads were very rough. | D.The temperature was not cold at all. |
A.Visitors. | B.Scooters. | C.Bicycle wheels. | D.Grassy mountains. |
A.The latest mild winter was in 1900. | B.Little snowfall has caused great economic loss. |
C.No one wants to ski because of the bad weather. | D.There’s something wrong with ski equipment. |
A.A medical report. | B.A tourist handbook. | C.A weather forecast. | D.An economic journal. |
【推荐2】In many countries, people work five eight-hour days or 40 hours a week. But some companies now want their employees to work just four days a week and still pay them for five. Is it too good to be true?
Planio, a German company, offered a four-day week to its employees earlier this year Schulz-Hofen, the founder of Planio, first tested the four-day workweek on himself. He said,“It is much healthier and we do a better job if we’re not working crazy hours. I didn't get less work done in four days than in five because in five days, you think you have more time, you take longer. ” Also, another company, called Guardian in New Zealand, tested how its employees reacted to a 32-hour workweek earlier this year. It said the workers reported feeling less pressured and more focused on the business.
In Japan, the government is urging companies to let their workers have Monday mornings off. And in the UK, Trades Union Congress (TUC) is pushing for the country to move to a four-day week by the end of the century, thinking that a shorter workweek is a way for workers to share in the wealth made by new technologies like machine learning and robotics. TUC’s Kate Bell noted,“It would reduce the stress of juggling working and family life. ’’
A study of 3, 000 employees found that nearly half thought they could easily finish their work in five hours a day if they did not have to stop and restart. The workers were from eight countries, including the United States,Britain and Germany. Dan Schawbel, working in Future Workplace, which carried out the survey with Kronossaid,“Because you always have the technology, you are always working, so you are getting burned out. He expects more companies and countries will permit a four-day workweek.
1. What did Schulz-Hofen do?A.He founded a company in the UK. |
B.He tried out a new idea himself. |
C.He made a study into Future Workplace. |
D.He urged his employees to be more productive. |
A.Stressful. | B.Beneficial. |
C.Unnecessary. | D.Faultless. |
A.Balancing. | B.Choosing. |
C.Improving. | D.Controlling. |
A.It is actually too good to be true. |
B.It has some unavoidable disadvantages. |
C.It is beneficial to both employees and companies. |
D.It has become a common practice in many countries. |
【推荐3】We think of hospitals as peaceful and safe places.
To prevent such things from happening, the government worked out a draft law. It says that the safety of medical staff is protected by law and that no one is allowed to hurt medical workers.
In most cases, the attackers were relatives of patients who were not satisfied with their treatment.
“When arguments happen, patients should ask for mediation (调解仲裁) or seek legal advice instead of turning to violence,” the State Council said.
A.Doctors need to take measures to protect themselves |
B.Most people have high expectations for their doctors |
C.Hospitals are trying to find ways to solve this problem |
D.Doctors in large public hospitals often have to overwork |
E.A general lack of trust in doctors has also made things worse |
F.It’s difficult to solve the problems between doctors and patients |
G.But doctors and nurses in Chinese public hospitals are often attacked |
【推荐1】There is a cute animal living in the rainforest of Central and South America. Hanging out in the trees is its regular routine. It eats plenty of leaves every day to maintain its body temperature, keeping its organs working. It has three toes and walks slowest. The giant panda is second slowest, and two-toed sloths (树懒) come in third. People are curious about why they walk slowest.
Three-toed sloths rely on leaves merely. They have evolved finely tuned strategies for coping with this restricted diet. Firstly, they get as much energy from their food as possible. Secondly, they have a multi-chamber stomach that takes up a third of their body. Thirdly, they can spend five to seven days, or even weeks, processing a meal.
The other distinguished feature of three-toed sloth is that they use as little energy as possible. They spend most of their time eating, resting or sleeping. They get down from the treetops once a week for a bathroom break. When sloths do move, it is not very fast. It would take a sloth about five minutes to cross an average neighborhood street.
This unhurried approach to life means that sloths don’t need very much muscle. In fact, they have about 30% less muscle mass than other animals of their size. They also use less energy to keep themselves warm because their body temperature can change by about five degrees Celsius, less than a cold-blooded reptile, but more than most mammals. These physical and behavioral adaptations minimize the sloth’s metabolic rate (新陈代谢率). Three-toed sloths have the slowest metabolism of any mammal.
Moving slowly has allowed sloths to grow in their treetQp habitat. But it also made the sloths themselves a great habitat for other organisms, including algae (藻类), which provides a little extra camouflage (保护色) and maybe even a snack.
1. What similarity do sloths and pandas have?A.Walking slowly. | B.Living in the rainforest. |
C.Having identical appearances. | D.Enjoying eating bamboo leaves. |
A.They frequently get down from trees. | B.They have rather small stomachs. |
C.They eat a variety of foods. | D.They digest food slowly. |
A.Their physical movement is faster than a cold-blooded animal’s. |
B.Their temperature is lower than other mammal’s of their size. |
C.Their muscle mass is more than other animals’. |
D.Their metabolism is the slowest of reptile’s. |
A.Why do three-toed sloths walk slowly? | B.Where is the habitat of three-toed sloths? |
C.What is the eating habit of three-toed sloths? | D.When will three-toed sloths come down from trees? |
【推荐2】Four Best Rock Drummers (鼓手) of All Time
Ginger Baker
Ginger Baker is a legendary drummer who was best known for his work with the band Cream. He was born in England in 1939, and he first gained fame in the 1960s for his innovative style and powerful technique. Baker was a master of jazz, rock, and African rhythms, and he was one of the first drummers to use double bass (低音) drums.
Phil Collins
Phil Collins rose to fame as the drummer for the rock band Genesis, but he soon became known as a solo artist in his own right.
One of Collins’ most symbolic moments is during the middle of the song In the Air Tonight. Collins plays a symbolic drum fill that even non-drummers collectively know how to play almost by instinct (本能). The drum fill was so impressive that it has been used in countless commercials and TV shows.
Keith Moon
Keith Moon was one of the most influential drummers of his generation. As a member of The Who, he helped pioneer a new drumming style characterized by its power and energy.
Moon was known for his aggressive playing style and willingness to take risks. For example, he often incorporated long drum fills into his playing. In addition, he was not afraid to experiment with new techniques.
Ringo Starr
Ringo Starr is best known as the drummer for the Beatles. But Ringo’s life didn’t start out on such an attractive note. He was born in Liverpool. England, in 1940. Ringo’s father left when he was three, and his mother soon died of cancer. Ringo was sent to live with his aunt, who was so poor that she often couldn’t afford to feed him. Yet, despite these difficult beginnings. Ringo persevered and went on to have a remarkable career.
1. Who was a member of Cream?A.Ginger Baker. | B.Phil Collins. | C.Keith Moon. | D.Ringo Starr. |
A.His innovative style. | B.His powerful technique. |
C.His use of double bass drums. | D.His drum fill in the song In the Air Tonight. |
A.He rose to fame early. |
B.He joined the Beatles in 1940. |
C.He had a hard life in his childhood. |
D.He was afraid to experiment with new techniques. |
【推荐3】Teen Art Show
Do you want to see your artwork displayed alongside other teens' artwork? Don't miss your opportunity! Showcase your paintings, sculptures, photographs and other artworks at the Environmental Educational Center. The show will provide an opportunity for artists to network, provide feedback and become a resource for others.
Location: Environmental Educational Center
Activity fee: $25
Night Fishing
Escape the night and join us as we fish at Desert Breeze Park. No experience needed. We will provide the fishing poles, transportation, the bait, help you catch a fish and best of all, teens 14 years and under do not require a license to fish.
Location: Desert Breeze Park
Activity fee: $22
Overnight Snow Trip
Join the City of Chandler in an exciting new trip! We will travel up to Camp Tontozona and enjoy great food and a campfire in the early evening. Snow play will be the highlight as we explore the snow-filled meadows(草地) of Woods Canyon Lake and sled down small hills in the area. You will be responsible for your own ski/snowboard equipment.
Location: Camp Tontozona
Activity fee: $30
Paintballing
Come out and play paintball with all your friends! Join the City of Chandler as we go to Tempe Indoor Paintball. This is a great way to join in the fun of playing paintball for a low, low cost. All equipment is included. Please wear old clothes because clothes can get dirty easily!
Location: Tempe Paintball
Activity fee: $28
1. In which activity should people take their own ski equipment?A.Overnight Snow Trip. |
B.Teen Art Show. |
C.Paintballing. |
D.Night Fishing. |
A.Meet with famous artists. |
B.Play with snow. |
C.Play paintball. |
D.Go fishing. |
A.It costs the least. |
B.It might make your clothes dirty. |
C.People can play with friends. |
D.People will enjoy a campfire. |